Allowing a lead to modify their email address on a landing page

[Caryl_Mostacho]

Hi 

Just wanted to ask if you send a contact that is already in your database to a marketo landing page. If they modify the email address that is shown on the landing page... will it create a new lead or will it modify the email address associated with their lead? 

[Anonymous]

Hi Caryl, 

By default it will create a new lead -- see detailed discussion here: https://community.marketo.com/MarketoDiscussionDetail?id=90650000000PapiAAC

The email is a primary key so new email would equal new lead. 

There are some ways around this via the API. To solve this using a Marketo form, one good suggestion I saw is to create an alternate field (e.g., "new email address") and have the lead update that. 

I believe you'd have to pre-populate a hidden field with the old email address to identify the correct record, then when the form submits with the new email address, have a campaign that runs to update the lead email address for that record to the token for the "new email address" field.